An unusual and unique instalment of Sherlock, The Sign of Three
is a complex, rip-roaring and extremely funny episode that takes
the series into tonally new territory, while preserving many of the
elements that we all love from the past.

It's no secret that the second episode of Series Three is
centred on the wedding of John Watson and Mary Morstan. It forms
the backbone of the narrative and setting, with the entire duration
dipping in and out of a critical part of the happy day through a
complicated branching structure that leads the characters, and us,
to some wildly unexpected places. Perhaps more so than any other
episode of Sherlock, this is the one that demands a repeat view to
truly appreciate the intricate nature of the events we're shown.
The script is credited to all three writers for the first time in
the series' history, with Steve Thompson leading, and elements of
the style of each are evident throughout the duration.

Following on from The Empty Hearse, the emphasis remains on the
relationship between the characters. There is delightful interplay
between the supporting cast, and a genuine further deepening of the
friendship between John and Sherlock, all expertly played by
Benedict Cumberbatch and Martin Freeman. The events at the end of
The Empty Hearse have solidified them. While we may have become
used to the notion of these characters living in the modern day,
The Sign of Three is the first time we see the pair fully enmeshed
in modern social culture - with surprising and utterly hilarious
results that may possibly provide more talking points than anything
in the series opener.

Like the preceding episode, while there is a central case in the
narrative, it is not immediately apparent, with over a third of the
duration of the episode running past until it fully forms. When it
does though, it's a story element that isn't engineered to serve
the characters in the same way that the terror plot of The Empty
Hearse is. Instead it's a good old fashioned mystery, a very
cleverly constructed piece of writing that allows both Sherlock and
John to shine in their unique ways, and highlights how dependent
they both are on the other now when placed into dangerous
situations. Mary continues to be an excellent addition to the cast
as well, Amanda Abbington a warm, wonderful presence who continues
to effortlessly interact with both the leading characters and is
utterly accepting of the wild and strange adventures the pair find
themselves thrust into.

The Sign of Three is visually astonishing to look at, featuring
true visual pizazz thanks to director Colm McCarthy. The entire
episode is infused with stand-out moments, including a memorable
and quite beautiful new introductory shot for 221B, a striking use
of split screen editing, and a dramatically different and new
visualisation of Sherlock's deductions. It also goes without saying
that the scoring of David Arnold and Michael Price continues to be
sonic delight, going into pulse-pounding and dramatic new places
that are unique to this instalment.

The warmest, funniest episode of Sherlock in existence, The Sign
of Three sees the series stepping quite boldly into broader comedic
tones and more emotional themes. The friendship of Sherlock and
John is clearly the front and centre of this new series, and
Sherlock's overt (and covert) reactions to the changes in John's
life give everything a subtly moving, powerful undercurrent. But
despite all the lightness and fun that infuses the episode, the
close brings us a few tiny flecks of foreboding for the series
finale in His Last Vow, and we can't help but feel the humour that
has defined the opening two parts of Sherlock Series Three is a
very clear and conscious presence due to what may lie ahead…